Simulation of temperature dependent dielectric breakdown in n{sup +}-polySi/SiO{sub 2}/n-6H-SiC structures during Poole-Frenkel stress at positive gate bias
We present for the first time a thorough investigation of trapped-hole induced gate oxide deterioration and simulation results of time-dependent dielectric breakdown (TDDB) of thin (7–25 nm) silicon dioxide (SiO{sub 2}) films thermally grown on (0 0 0 1) silicon (Si) face of n-type 6H-silicon carbide (n-6H-SiC). Gate oxide reliability was studied during both constant voltage and current stress with positive bias on the degenerately doped n-type poly-crystalline silicon (n{sup +}-polySi) gate at a wide range of temperatures between 27 and 225 °C. The gate leakage current was identified as the Poole-Frenkel (PF) emission of electrons trapped at an energy 0.92 eV below the SiO{sub 2} conduction band. Holes were generated in the n{sup +}-polySi anode material as well as in the oxide bulk via band-to-band ionization depending on the film thickness t{sub ox} and the energy of the hot-electrons (emitted via PF mechanism) during their transport through oxide films at oxide electric fields E{sub ox} ranging from 5 to 10 MV/cm. Our simulated time-to-breakdown (t{sub BD}) results are in excellent agreement with those obtained from time consuming TDDB measurements. It is observed that irrespective of stress temperatures, the t{sub BD} values estimated in the field range between 5 and 9 MV/cm better fit to reciprocal field (1/E) model for the thickness range studied here. Furthermore, for a 10 year projected device lifetime, a good reliability margin of safe operating field from 8.5 to 7.5 MV/cm for 7 nm and 8.1 to 6.9 MV/cm for 25 nm thick SiO{sub 2} was observed between 27 and 225 °C.
- OSTI ID:
- 22597670
- Journal Information:
- Journal of Applied Physics, Vol. 120, Issue 6; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA); ISSN 0021-8979
- Country of Publication:
- United States
- Language:
- English
Similar Records
Characteristics of n{sup +} polycrystalline-Si/Al{sub 2}O{sub 3}/Si metal{endash}oxide{endash} semiconductor structures prepared by atomic layer chemical vapor deposition using Al(CH{sub 3}){sub 3} and H{sub 2}O vapor
Dynamics of field effect devices with ultra thin YBaCuO/PrBaCuO multilayer channels
Related Subjects
GENERAL PHYSICS
ANODES
BREAKDOWN
DIELECTRIC MATERIALS
DOPED MATERIALS
ELECTRIC FIELDS
ELECTRONS
EMISSION
FILMS
HYDROGEN 6
LEAKAGE CURRENT
NITROGEN IONS
RELIABILITY
SILICA
SILICON CARBIDES
SILICON OXIDES
SIMULATION
STRESSES
TEMPERATURE DEPENDENCE
THICKNESS
TIME DEPENDENCE